All times are local unless otherwise stated.

Cleveland (United States) | 18 July-24 July 2007 | New Activity / Unrest Cite this Report
Cleveland Aleutian Ridge Volcanic Arc	AVO raised the Volcanic Alert Level for Cleveland from Advisory to Watch and the Aviation Color Code from Yellow to Orange on 20 July. The change in Alert Level was based on the presence of an intense thermal anomaly in the crater and associated steam-and-gas plume observed on satellite imagery. The thermal anomaly continued to be detected on satellite imagery during 22-23 July. Source: US Geological Survey Alaska Volcano Observatory (AVO)
Fuego (Guatemala) | 18 July-24 July 2007 | New Activity / Unrest Cite this Report
Fuego Central America Volcanic Arc	INSIVUMEH reported that during 17-18 July, gas plumes from Fuego rose to an altitude of 3.9 km (12,800 ft) a.s.l. and drifted SW. On 18 July, a hot lahar, 20 m wide and 1.5 m high, carried blocks 1-1.5 m in diameter to the W down the Santa Teresa ravine. On 20 July, the seismic network recorded 21 explosions. Associated ash plumes rose to altitudes of 4.1-4.7 km (13,500-15,400 ft) a.s.l. and drifted W and SW. Rumbling noises were reported. CONRED raised the Alert Level to Yellow in surrounding communities on 22 July, based on a report from INSIVUMEH. INSIVUMEH reported that Vulcanian explosions produced ash plumes to altitudes of 4.1-5.2 km (13,500-17,100 ft) a.s.l. and expelled incandescent material 75-250 m above the crater. The explosions were accompanied by rumbling noises and shock waves that rattled ceilings and windows within a 25 km radius. Ashfall was reported from areas approximately 7-8 km to the SW, and incandescent avalanches of blocks rolled 500-800 m down the S flanks towards areas of vegetation. A new lava flow that initiated from an area 100 m below the S edge of the central crater traveled about 100 m. Sources: Coordinadora Nacional para la Reducción de Desastres (CONRED), Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH)
Kilauea (United States) | 18 July-24 July 2007 | New Activity / Unrest Cite this Report
Kilauea Hawaiian-Emperor Hotspot Volcano Group	During 18-21 July, the E vent and dominant W vent in Kilauea's Pu'u 'O'o produced lava flows. On 18 July, new vents opened in the Puka Nui pit, in the SSW area of Pu'u 'O'o crater, and produced lava flows that ponded. On 20 July, a vent high on the S crater wall, adjacent to the Puka Nui Gap pit, produced spatter and propelled lava bombs 10 m into the air. Meanwhile, the lava lake in the West Gap pit continued to fill, overturn, and occasionally overflow. The spatter cone that built up around the S wall vent in West Gap pit was submerged beneath the lava lake surface on 20 July. Uplift of the crater interior continued. Earthquakes occurred beneath the upper E rift zone, S flank, and Halema'umau crater. On 20 July, just before midnight, Pu'u 'O'o's crater floor started to subside; a tiltmeter recorded a nearly 300 microradian tilt change. Just after midnight, on 21 July, the West Gap lava lake and Puka Nui pit drained. A new eruption initiated along a set of fissures that extended 1.7 km E from a point about 150 m E of the E rim of Pu'u 'O'o crater. Preliminary reports described two 600-800 m long, left-stepping fissures between Pu'u 'O'o and Kupaianaha. The easternmost fissure fed two lava flows; the farthest extent of the flow was 1-1.5 miles from the fissure in the SE direction. On 22 July, HVO reported that the westernmost fissure was inactive by mid-morning on 21 July and the uppermost segment of the active lower fissure was completely sealed by mid-morning on 22 July. The rest of the fissure erupted lava, constructing several small perched ponds. A perched pond at the upper segment of the active fissure breached and produced an a'a' flow that traveled 300-400 m to the E. At Pu'u 'O'o crater, several new cracks were observed around its rim, parts of which had collapsed. During 23-24 July, lava ponds surrounding lower fissure segments grew in thickness and spilled lava over their edges. Source: US Geological Survey Hawaiian Volcano Observatory (HVO)
Ol Doinyo Lengai (Tanzania) | 18 July-24 July 2007 | New Activity / Unrest Cite this Report
Ol Doinyo Lengai Kenyan Rift Volcanic Province	According to news reports, an eruption began at Ol Doinyo Lengai around 19 July, forcing villagers living near the volcano to evacuate. An article stated that, "...more than 1,500 people, most of them Maasai families, vacated their homes in Ngaresero, Orbalal and Nayobi villages following the tremors that triggered the volcanic eruption." "Villagers are reported to have heard roaring...before the volcano started discharging ash and lava." There were reports of a damaged school and two injuries, but no reports of deaths. Sources: Associated Press, East African Standard

Karymsky (Russia) | 18 July-24 July 2007 | Continuing ActivityCite this Report
Karymsky Eastern Kamchatka Volcanic Arc	Seismic activity at Karymsky was above background levels during 13-20 July, with 500-900 shallow earthquakes occurring daily. Based on seismic interpretation, ash plumes may have risen to altitudes as high as 4.5 km (14,800 ft) a.s.l. Ash plumes drifted SE and SW and a thermal anomaly in the crater were visible on satellite imagery during 14-18 July. Plumes rose to estimated altitudes of 4.5 km (14,800 ft) a.s.l. based on atmospheric profiles. The Level of Concern Color Code remained at Orange Based on satellite imagery, the Tokyo VAAC reported that an ash plume rose to an altitude of 5.2 (17,000 ft) a.s.l. on 20 July and drifted SW. Sources: Kamchatkan Volcanic Eruption Response Team (KVERT), Tokyo Volcanic Ash Advisory Center (VAAC)
Klyuchevskoy (Russia) | 18 July-24 July 2007 | Continuing ActivityCite this Report
Klyuchevskoy Eastern Kamchatka Volcanic Arc	KVERT reported that seismic activity at Kliuchevskoi was at background levels during 13-20 July. Based on observations of satellite imagery, ash plumes drifted E on 13 July and a thermal anomaly in the crater was noted during 13-20 July. Ash plumes rose to an altitude of 5.5 km (18,000 ft) a.s.l. and drifted SE and E during 13-15 July, according to video and visual observations. Gas-and-steam plumes were observed on 12, 16, and 18 July. The Level of Concern Color Code was lowered from Orange to Yellow due to a decrease in seismicity and an absence of ash plumes during 17-20 July. Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Lascar (Chile) | 18 July-24 July 2007 | Continuing ActivityCite this Report
Lascar Central Andean Volcanic Arc	Based on pilot reports and satellite image observations, the Buenos Aires VAAC reported that an ash plume from Lascar rose to altitudes of 7.6-9.1 km (25,000-30,000 ft) a.s.l. on 18 July and drifted NE. Source: Buenos Aires Volcanic Ash Advisory Center (VAAC)
Sangay (Ecuador) | 18 July-24 July 2007 | Continuing ActivityCite this Report
Sangay Northern Andean Volcanic Arc	Based on pilot observations, the Washington VAAC reported that an ash plume from Sangay rose to an altitude of 5.5 km (18,000 ft) a.s.l. and drifted W on 23 July. Ash was not detected on satellite imagery. On 24 July, a diffuse ash plume at an altitude of 5.2 km (17,000 ft) a.s.l. was visible on satellite imagery drifting SW. Source: Washington Volcanic Ash Advisory Center (VAAC)
Sheveluch (Russia) | 18 July-24 July 2007 | Continuing ActivityCite this Report
Sheveluch Eastern Kamchatka Volcanic Arc	KVERT reported that seismic activity at Shiveluch continued above background levels during 13-20 July. Based on seismic interpretation, ash plumes rose to an altitude of 6 km (19,700 ft) a.s.l. during the reporting period. Gas-and-steam plumes with some ash rose to altitudes of 3-4.5 km (9,800-14,800 ft) a.s.l. during 11-15 and 18-19 July. Based on satellite imagery, plumes drifted S and SW during 15-16 July and a large thermal anomaly was detected in the crater during 13-20 July. The Level of Concern Color Code remained at Orange. Based on information reported from KEMSD, the Tokyo VAAC reported that an eruption plume rose to 5.8 km (19,000 ft) a.s.l. on 24 July. Ash was not identified on satellite imagery. Sources: Kamchatkan Volcanic Eruption Response Team (KVERT), Tokyo Volcanic Ash Advisory Center (VAAC)
Soufriere Hills (United Kingdom) | 18 July-24 July 2007 | Continuing ActivityCite this Report
Soufriere Hills Lesser Antilles Volcanic Arc	MVO reported that during 13-24 July, the lava dome at Soufrière Hills changed very little, based on visual observations. Seismic activity was very low and low-level rockfall activity continued. Heavy rainfall generated lahars in E drainages on 19 July. The Alert Level remained elevated at 4 (on a scale of 0-5). Source: Montserrat Volcano Observatory (MVO)
St. Helens (United States) | 18 July-24 July 2007 | Continuing ActivityCite this Report
St. Helens High Cascades Volcanic Arc	Data from deformation-monitoring instruments indicated that during 18-24 July lava-dome growth at Mount St. Helens continued. Seismicity persisted at low levels, punctuated by M 1.5-2.5, and occasionally larger, earthquakes. Clouds inhibited visual observations. Source: US Geological Survey Cascades Volcano Observatory (CVO)
Tungurahua (Ecuador) | 18 July-24 July 2007 | Continuing ActivityCite this Report
Tungurahua Northern Andean Volcanic Arc	IG reported that during 18-24 July, intermittently visible ash plumes from Tungurahua rose to altitudes of 5.2-8 km (17,100-26,200 ft) a.s.l. and drifted NW, W, and SW. Ashfall was reported from areas SW and W during 19-21 and 24 July. On 20 July, mudflows were reported from drainages to the NW. On 21 July, a steam-and-gas plume drifted W. On 21, 22, and 24 July, ash plumes were occasionally accompanied by roaring sounds, "cannon shots", or noises that resembled blocks rolling down the flanks. Source: Instituto Geofísico-Escuela Politécnica Nacional (IG-EPN)
Ubinas (Peru) | 18 July-24 July 2007 | Continuing ActivityCite this Report
Ubinas Central Andean Volcanic Arc	Based on a Significant Meteorological Information (SIGMET) advisory, the Buenos Aires VAAC reported that an ash plume from Ubinas rose to an altitude of 6.1 km (20,000 ft) a.s.l. and drifted SE on 22 July. Ash was not identified on satellite imagery. Source: Buenos Aires Volcanic Ash Advisory Center (VAAC)

Weekly Reports Archive

Since the Weekly Volcanic Activity Report began in November 2000, there have been 20,627 individual reports over 1,243 weeks (average of 17 per week) on 338 different volcanoes.

Use the dropdowns to choose the year and week for archived Weekly Reports.

 News Feeds and Google Placemarks

 Criteria & Disclaimers

The Weekly Volcanic Activity Report does not necessarily include all volcanic activity that occurred on Earth during the week. More than a dozen volcanoes globally have displayed more-or-less continuous eruptive activity for decades or longer, and such routine activity is typically not reported here. Moreover, Earth's sea-floor volcanism is seldom reported even though in theory it represents the single most prolific source of erupted material. The Weekly Volcanic Activity Report summarizes volcanic activity that meets one or more of the following criteria:

- A volcano observatory raises or lowers the alert level at the volcano.
- A volcanic ash advisory has been released by a volcanic ash advisory center (VAAC) stating that an ash cloud has been produced from the volcano.
- A verifiable news report of new activity or a change in activity at the volcano has been issued.
- Observers have reported a significant change in volcanic activity. Such activity can include, but is not restricted to, pyroclastic flows, lahars, lava flows, dome collapse, or increased unrest.

Volcanoes are included in the "New Activity/Unrest" section of the Weekly Volcanic Activity Report if the activity occurs after at least 3 months of quiescence. Once a volcano is included in the "New Activity/Unrest" section, updates will remain in that section unless the activity continues for more than 1 month without escalating, after which time updates will be listed in the "Continuing Activity" section. Volcanoes are also included in the "New Activity/Unrest" section if the volcano is undergoing a period of relatively high unrest, or increasing unrest. This is commonly equal to Alert Level Orange on a scale of Green, Yellow, Orange, Red, where Red is the highest alert. Or alert level 3 on a scale of 1-4 or 1-5.

It is important to note that volcanic activity meeting one or more of these criteria may occur during the week, but may not be included in the Weekly Volcanic Activity Report because we did not receive a report.

1. The Weekly Volcanic Activity Report is intended to provide timely information about global volcanism on a weekly basis. Consequently, the report is generated rapidly by summarizing volcanic reports from various sources, with little time for fact checking. The accuracy of the Weekly Volcanic Activity Report is dependent upon the quality of the volcanic activity reports we receive. Reports published in the Bulletin of the Global Volcanism Network are cover longer time periods and are more carefully reviewed, although all of the volcanoes discussed in the Weekly Volcanic Activity Report are not necessarily reported in the Bulletin. Because of our emphasis on rapid reporting on the web we have avoided diacritical marks. Reports are updated on the Weekly Volcanic Activity Report web page as they are received, therefore information may be included regarding events that occurred before the current report period.

2. Rapidly developing events lead to coverage that is often fragmentary. Volcanoes, their eruptions, and their plumes and associated atmospheric effects are complex phenomena that may require months to years of data analysis in order to create a comprehensive summary and interpretation of events.

3. Preliminary accounts sometimes contain exaggerations and "false alarms," and accordingly, this report may include some events ultimately found to be erroneous or misleading.

4. Many news agencies do not archive the articles they post on the Internet, and therefore the links to some sources may not be active. To obtain information about the cited articles that are no longer available on the Internet contact the source.

5. USGS Disclaimer Statement for this Website:

Information presented on this website is considered public information and may be distributed or copied. Use of appropriate byline/photo/image credit is requested. We strongly recommend that USGS data be acquired directly from a USGS server and not through other sources that may change the data in some way. While USGS makes every effort to provide accurate and complete information, various data such as names, telephone numbers, etc. may change prior to updating. USGS welcomes suggestions on how to improve our home page and correct errors. USGS provides no warranty, expressed or implied, as to the accuracy, reliability or completeness of furnished data.

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U.S. Department of the Interior, U.S. Geological Survey, Reston, VA, USA
URL: https://volcano.si.edu/reports_weekly.cfm

 Acronyms and Abbreviations

a.s.l. - above sea level

AVO - Alaska Volcano Observatory

AVHRR - Advanced Very High Resolution Radiometer

CENAPRED - Centro Nacionale de Prevencion de Desastres (México)

CONRED - Coordinadora Nacional para la Reducción de Desastres

COSPEC - Correlation Spectrometer

CVGHM (formerly VSI) - Center of Volcanology and Geological Hazard Mitigation

CVO - Cascades Volcano Observatory (USGS)

GMS - Geostationary Meteorological Satellite

GOES - Geostationary Operational Environmental Satellite

GVO - Goma Volcano Observatory

GVP - Global Volcanism Program (Smithsonian Institution)

HVO - Hawaiian Volcano Observatory (USGS)

ICE - Instituto Costarricense de Electricidad (Costa Rica)

IG - Instituto Geofísico (Ecuador)

IGNS - Institute of Geological and Nuclear Sciences (New Zealand) - now GNS Science

INETER - Instituto Nicaragüense de Estudios Territoriales (Nicaragua)

INGEMMET - Instituto Geológical Minero y Metalúrgico (Peru)

INGEOMINAS - Instituto Colombiano de Geología y Minería (Colombia)

INGV-CT - Istituto Nazionale di Geofisica e Vulcanologia - Sezione di Catania (Italy)

INSIVUMEH - Instituto Nacional de Sismologia, Vulcanologia, Meteorologia e Hidrologia (Guatemala)

IRD - Institut de Recherche pour le Développement (France)

JMA - Japanese Meteorological Agency

KEMSD - Kamchatkan Experimental and Methodical Seismilogical Department

KVERT - Kamchatkan Volcanic Eruption Response Team

M - magnitude

METEOSAT - Meteorological Satellite

MEVO - Mount Erebus Volcano Observatory

MODIS - Moderate Resolution Imaging Spectroradiometer

MVO - Montserrat Volcano Observatory

MWO - Meteorological Watch Office

NEIC - National Earthquake Information Center

NIED - National Research Institute for Earth Science and Disaster Prevention (Japan)

NOAA - National Oceanic and Atmospheric Administration

NOTAM - Notice to Airmen

OVDAS - Observatorio Volcanologico de los Andes del Sur (Chile)

OFDA - Office of US Foreign Disaster Assistance

ONEMI - Oficina Nacional de Emergencia - Ministerio del Interior (Chile)

OVPDLF - Observatoire Volcanologique du Piton de la Fournaise (France)

OVSICORI-UNA - Observatorio Vulcanologico y Sismologico de Costa Rica, Universidad Nacional (Costa Rica)

PHIVOLCS - Philippine Institute of Volcanology and Seismology (Philippines)

RSAM - Real-time Seismic Amplitude Measurement

RVO - Rabaul Volcano Observatory

SERNAGEOMIN - Servicio Nacional de Geologia y Mineria (Chile)

SIGMET - Significant Meteorological Information

SNET - Servicio Nacional de Estudios Territoriales (El Salvador)

SVERT - Sakhalin Volcanic Eruption Response Team (Russia)

USAID - US Agency for International Development

USGS - United States Geological Survey

UTC - Coordinated Universal Time

VAAC - Volcanic Ash Advisory Center

VAFTAD - Volcanic Ash Forecast Transport And Dispersion

VDAP - Volcano Disaster Assistance Program (USGS)

VHP - Volcano Hazards Program (USGS)

VRC - Volcano Research Center (Japan)